The neurobiological alterations resulting from adverse childhood experiences that subsequently may lead to worse health, anti-social behavior, and even later neglectful parenting are poorly understood. Maternal neglect of an infant?s basic needs is the most prevalent type of child maltreatment. We examine whole genome DNA methylation and specific gene regions of neglectful mothers and their children, and compare them to a matched control group. 275 participants (144 mothers and 133 of their children) were recruited to provide behavioral information and saliva samples for analysis. Participants were recruited from San Cristobal de La Laguna, Tenerife Island of the Canary Islands, Spain. Neglectful mothers were all attending a preventive parenting program delivered by the municipal social services. Control mothers were drawn from the same neighborhoods but without neglectful parenting behavior. The group of neglectful mothers was highly homogeneous: a) their primary identified problem was substantiated neglect of a child under five years old according to the Maltreatment Classification System ; b) all mothers in this group exhibited the three main subtypes of neglect: physical neglect, lack of supervision and educational neglect; c) all had a history of maltreatment, while none had severe mental health problems (e.g. depression), were drug abusers and/ or had a low IQ according to the social services. If they had had such problems, the social services would have received a report from the mental health services. All mothers in the control group had at least one child under five years old, a confirmed absence of neglectful behavior in the social services records and no severe mental health concerns. An analysis of key demographic variables revealed that the mothers in the neglectful and the control groups did not significantly differ on any variable.